Three-phase oscillator



May 11,1926. 1 1,584,490

' A. H. TAYLOR THREE-PHASE] OSCILLATOR Filed Nov. 50. 1925 1 IA YENTOR. A ar/1% fly/oz' ATTORNEY 20 being arranged to maintain the currents in tions.

Patented May 11 1926. i 1 p I V UNITED STATES PATENT FFICE.;

ALBERT H. TAYLOR, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR TO"WIRED RADIO, INCL, OF NEW -YORK, N. Y.', A CORPORATION OF DELAWARE.

THREE-PHASE OSCILLATOR. Application filed November 30, 1925. Serial No. 72,412.

My invention relates broadly to high oscillator in one of the phases of the'sysfrequency generators and more particularly tem, while the other phases are arranged to to an electron tube generator of three phase be self-oscillatory; and Fig. 3 is a vector oscillations. I diagram illustrating the phase displace 6 One of the objects of my invention is to ment of the currents in each of the phases provide acompact circuit arrangement, of the Y connected system.

, whereby electron tubes may be arranged The three phase oscillator of my invenfor the generation of three phase high fretion employs sets of electron tubes each arquency currents and the currents in the sevranged in separate phases of the high fre- 10 eral phases displaced 120 angular degrees at quency generating system and each having constant frequency. an independent input circuit and a separate A th bj t f my i ti i t rooutput C1I'Cll1t with the output circuit convide an electron tube generator for three nectcd in Y and arranged to deliver the enphase high frequency oscillations, in which orgy from the several electron tube genthe constant frequency characteristics of to a Connected WOIk circuit h piezo electric crystals are utilized for regu three phase high frequency energy thus genlating the phase displacement of currents crated maybe used in systems of wired rawhich are impressed upon a Y connected die or in space radio systems set forth more output circuit, the piezo electric crystals -p ar 1c u1 ar1 1n the aforementionedapplicathe Y connectedcircuit at a displacement of Referring to the drawings in molie detail, 120 d reference characters 1, 2 and 3 designate M i ti fi d ti l li ti separate electron tubes, each having grid,

as a source f th phase hi h frequency filament and plate electrodes, as represented .25 energy. employed in Systems uch as set in. case electron tube 1 elecso f th i R b t 1) D J P t t trode 1, filament electrode 1 and plate 1,560,505, dat d N b 3, 1925, d in electrode 1. Each of the tubes has an inde-' the systems in co-pending application filed Pendent F2 cllcult 5 and 6 and separate by Robert D. Duncan, J r., Serial No. 35,212, ou put clrcults 7, 8 and 9. In Fig. 1, I have 30 filed June 5, 1925, entitled Three phase Illu rated, e ch otthe input circuits as 0011 wired radio receivin circuits; application fi y osclllatwns d v lop d by piezo Serial No. 45,131, 'fi ed July 21, 1925, by electric crystals 1Q, 11 and 12 R b 1 Duncan, J f th Phase hi h electr ccrystal is arranged 1n ser1es with frequency system; application Serial No.- si t1zing choke 14 and the oscillating cir- 45,1 1 fil d J l -21, 1925, b R b t 1), cuit is shunted by'radio frequency choke 15 Duncan, J in, Samuel Isler and Salvatore A. Serles Wlth theisourc? f negat1Ve p B f three phase hi h frequency tial 16. The output circuit 7 of. electron tem; and application Serial No. 45,948, filed tllbe 1 Contams Inductance 17 tulled y July 24, 1925,, by Robert D. Duncan, Jr., for 11517016 condenser The output circuit-8 d l di t l h t m, of electron-tube 2 00111221118 inductance 19 05 M i ti ill b -f ll d tuned by variable condenser 20. The outstood from the specificationhereinafter folput circuit 9 of electron tube 3 contains inlowing by reference to the accompanying ductance 21 tuned by means of variable condrawings, in which: 1 denser 22. The inductances 17, 19 and 21.

Figure l'illustrates the principle of my are connected in Y. A series feed system is invention embodied in a Y connected 'oscilprovided for supplying plate voltage to the lation circuit, where piezo olectric crystal several tubes from a common source 23 elements are arranged to control the phase shunted by radio frequency by-pass condisplacement'ofthe currents in each of the denser 24, with a connection from the source 1 phases; Fig." 2 illustrates a modified ar- 23v to ground 25, The inductances- 17, 19 'rangei'nent of a Y connected three phase and 21 are coupled with secondary inducoscillator circuit, in which the phase distances 28, 29 and 30 respectively, which inplacement of the currents in the Y connected ductances are connected in Y and extend tocircuit are displaced degrees apart un-' a suitable distribution circuit which I have 'de'r' control of 'a' single piezo electric crystal represented ascomprising lines L, L and intermediate amplifi L upon which the three phase high frequency oscillations are impressed. The center of the Y connected" system may be ground "at 26, through condenser 27. Reaction will inevitably be present between the three primaries 17 ,19 and 21, where the inductances are arranged in Y and each tuned independently by condensers 18, 20

and 22. By reason of the reaction the currents in the phases of the three single phase oscillators will adjust themselves to 120 angular degrees apart, as represented in Fig. 3. The arrangement of the distribution circuit is such that when the high frequency load is applied to the line wire system the reaction between the three oscillators will be emphasiZe'd'and reduces the tendency of an oscillator to put energy into any one oscillator or subtract from it, thus advancing or retracting its phase. 7

The three phase high frequency load may be applied to the work circuit comprising lines L, L and L in any one of two ways. The high frequency load may be connected between L and ground, between L and ground, and L and ground if desired, or between L and L, L and L, and L? and The first method is preferable, where ers are used. The center of the Ywhich is connected through condenser 27 to ground 26, makes it possible to connect the filament of any tube to ground and excite amplifier from L be connected to L the grid of said Another amplifier can and a third one to If,

I and there can be several stages of amplifi- What I claim and cation in each group if desirable. The output of this oscillator rna thus be used to excite the power ampli ers in the three phase arrangement or to feed directly into three antennae or three wires of a transmission line system. S

In Fig. 2 I have shown a three phase Y connected system, where two of the phases comprising tubes 2 and 3 are self-excited and not crystal controlled, enabling these oscillators to shift slightly in frequency in order that the desired 120 degree phase displacement may be established, which is then maintained at constant frequency by virtue of the operation of the piezo electric crystal 10 in the circuit of the oscillator 1. p I have illustrated-the phase oscillator system .in one of its preferred embodiments, but I desire that it be understood that several sets of electron tubes may be employed in each of the oscil lator circuits for increasin the amplitude of the high frequency signa ing energy.

desire to secure by Let ters Patent of the United States is as follows:

1. A three phase oscillator comprising in combination t ree independent sets of electron tubes, each having independent output power amplifier tential connected with each Y connected three circuits for generating single phase current, Y connected igh fre uency circuits with the out ut circuits of eac of said tubes coupled wit said Y connected high frequency circuits and constant frequency elements for of the' electron tubes in said Y connected circuits. three phase controlling the frequency of each 2. In a system for generating oscillations, the combination of a set of three independent single phase oscillators, a Y connected circuit connected with said oscillators, and a piezo electric crystal arranged to control the phase displacements of the currents in said Y connected circuit.

- 3. A three phase high frequency oscillator, comprising in combination a grou of three inde endent electron tubes each having grid, lament and plate electrodes, input and output circuits mterconnectin said electrodes, a set of Y connected hig frequency circuits, connections between each of said output circuits and said Y connected circuits, and a mechanically vihratile element connected in at least one of said input circuits for controlling the output of each of said electron tubes, and for maintaining the 120 degree displacement of the currents supplied to said Y connected circuits.

4. In a system for generating three phase high frequency currents, the combination of a set of -Y connected circuits, means for tuning each branch of said circuits, a grou of three independent electron tubes, eacr having grid, lament and plate electrodes, an output circuit interconnecting said plate and filament electrodes, each other, an input circuit interconnecting said grid and filament electrodes independently of each other, means out ut circuit of each of said electron tubes wit a tuned branch of said Y connected circuits, a constant frequency generator of oscillations connected in each" of said input circuits, and a common source of high poof said output circuits for the supply of power to said circuits.

5. In a sy phase high frequency oscillations the combination of three independent electron tubes each having grid, filament and plate electrodes, input circuits including the grid and filament electrodes of each of said tubes, output circuits including the plate and filament electrodes of each of said tubes, in-

ductances in each of said output circuits,

a Y connected circuit including said inductances, a Y connected high potential circuit for supplying operating voltages to each of said output circuits, separate piezo electric crystals ground to the same frequency connected in the input circuits of each of said for coupling the I independently of l stem for the generation of three high frequency energy may be impressed .upon said power distribution circuit and the currents in each of the phases being displaced 120 degrees apart by operation of said piezo electric crystals.

6. In a system for the phase high frequency oscillations, the combination of three independent electron tubes each having grid, filament and plate electrodes, input circuits including the grid and filament electrodes of each of said tubes, output, circuits including the plate and fila ment electrodes of each of said tubes, inductances in each of said output circuits, a Y connected circuit including said inducgeneration of three trio crystal, a Y

tances, a Y connected high otential circuit for supplying operating v0 tage to each of said output circuits, at least one of said input circuits being controlled by a piezo'elec connected power distribut1on circuit inductively coupled with each of said in'ductances respectively and ground ed at the center point thereof, whereby three' phase oscillations maybe impressed upon said line wire distributionbircuitunder control of said piezo electric crystal and the em ergy utilized between a connection to ground and any ide of said power distribut1on circuit.

,. ALBERT H. TAYLOR. 

